The present invention relates generally to a technique which, in a musical instrument provided with a sound board to which physical vibrations of a sounding member like a string are transmitted, permits recording of a vibration waveform related to vibrations of the sound board, and also relates to a sound reproduction apparatus, such as a musical instrument like a piano, capable of generating an audible sound by vibrating a sound board in accordance with a drive signal indicative of a vibration waveform of the sound board.
Examples of the conventionally-known pianos include ones known, for example, from Japanese Patent Application Laid-open Publication No. HEI-5-73039 and Published Japanese Translation of International Patent Application No. 2006-524350, which can compulsorily vibrate a sound board by an actuator in accordance with a drive signal in addition to vibrations caused by striking of strings.
In the piano disclosed in Japanese Patent Application Laid-open Publication No. HEI-5-73039, vibrations of any one of the strings and the sound board during a performance are detected via vibration sensors and a microphone, DSP processing is performed on the detected vibrations to generate a sound board drive signal so that the actuator is driven to vibrate the sound board within five msec from sound generation by striking of the string. Thus, a sound generated by vibrations of the sound board via the actuator is added to a sound of an acoustic piano, so that it is possible to set as desired a type and variation amount of an audio effect to be imparted in a performance.
However, with the piano disclosed in Japanese Patent Application Laid-open Publication No. HEI-5-73039, where the sound board and the strings are in such a relationship that vibrations are transmitted mutually between them, a resonant sound resulting from compulsory vibrations of the sound board etc. are generated in addition to a sound generated by striking of any one of the strings. Thus, the sound generated by the string striking and the sound by the compulsory vibrations of the sound board mix together to cause a resonant-sound overlapping state, so that an unintended acoustic effect may be undesirably produced.
Because sounds of different quality from original sounds of the acoustic piano are generated for the foregoing reason, the technique disclosed in the No. HEI-5-73039 publication differs from a technique intended to faithfully replicate or reproduce original acoustic characteristics of an acoustic piano in a performance. In addition, the technique disclosed in the No. HEI-5-73039 publication is not a technique designed to execute automatic reproduction using data obtained by recording a performance. Further, because the technique disclosed in the No. HEI-5-73039 publication is constructed to merely generate sounds by compulsory vibrations of the sound board in addition to sounds generated by string striking, it can hardly adjust sound volumes during a performance. Further, Published Japanese Translation of International Patent Application No. 2006-524350 does not disclose recording and reproducing vibrations of the sound board.